Hi Tibono,
'quick'? That's more than complicated and would need extra Polyglot files (exe, ini) for EVERY MessChess engine - definitely not a method for a normal user! You (and everyone else) should really better stay with Arena, BearChess, Hiarcs, Shredder etc., which work without problems.
No, although the UCI implementation in MessChess (init.lua) is of course not complete, it contains all basic features that are needed to successfully run the MAME emulations (as you can see with all other GUIs mentioned above).

Nevertheless thanks for your test, which has once again encouraged me to steer clear of the Fritz GUI.

Regards,
Franz

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